This simple circuit can be used as an aid for sensing the distance between the rear bumper of the car and any obstacle behind the car. The distance can be understood from the combination of the LEDs (D5 to D7) glowing. At 25cm D7 will glow, at 20 cm D7&D6 will glow and at 5cm D7, D6 and D5 will glow. When the obstacle is beyond 25 cm none of the above LEDs will glow.

Two ICs are used in the circuit. The IC1 (NE555) is wired as an astable multivibrator for driving the IR Diode D1 to emit IR pulses. The operating frequency of the transmitter is set to be 120Hz.The IR pulses transmitted by D1 will be reflected by the obstacle and received by the D2 (IR photo diode).The received signal will be amplified by IC2a.The peak of the amplified signal will be detected by the diode D4 and capacitor C4.R5 and R6 compensates the forward voltage drop of D4.The output voltage of the peak detector will be proportional to the distance between car’s bumper and obstacle. The output of peak detector is given to the inputs of the other three comparators IC2b,IC2c and IC2d inside the IC2 (LM324).The comparators switch the status LEDs according to the input voltage their inverting inputs and reference voltages at their non inverting inputs. Resistances R7 to R10 are used to set the reference voltages for the comparators.

Circuit diagram with Parts list.

Notes.

Assemble the circuit on a good quality PCB or common board.

The D1 & D2 must be mounted close (~2cm) to each other, looking in same direction.

The D1 can be a general purpose IR LED.

The D2 can be general purpose IR photo diode with sun filter.

The transmitter as well as receiver can be powered from the car battery.

For proper working of the circuit, some trial and error is needed with the position of D1 and D2 on the dash board.

@hai – Since you have bought a manufactured product, its very hard to edit its program and reduce the distance to 1 meter. The option you have got is to build a customized circuit for yourself using a controller like 8051 or AVR or even Arduino and adjust the distance to suit yourself. But it highly depends on your skill in electronics and programming. Please be informed that you can’t edit the code inside your Amazon bought product!

Hi sir,we doing this as our final year project…Need more information about PCB layout, requiring components and working…how to install it on a actual vechicle ….can you please send those details to my mail and it will very helpful for us…thank you

hellow sir,should i use only a 12v source for it or shall i use 9v source….and i also have another prblm,once after connecting the receiver circuit all my LED glows,even when transmitter is swicthed off…what may be my prblm????

This circuit works perfectly with some modifications. However this circuit is not suitable for reverse parking because the IRs are reflected in Daylight if you adjust it for daytime then for night you have to adjust the sensitivity again. It will be better if you use ultrasonic Sensors.

Sir,
I have taken the above circuit for my mini project.
can u pls send me the details of the circuit with LED and Buzzer, it’s working and pcb schematics on my email.
My email is nglaiboon@hotmail.com

Sir,
I have taken the above circuit for my mini project.
I hope that the circuit works…
can u please send me the details of the circuit, it’s working and pcb schematics..?
I badly need them…urgently
my mail id is as above
please send the details…

Sir,
I have taken the above circuit for my mini project.
I hope that the circuit works…
can u please send me the details of the circuit, it’s working and pcb schematics..?
I badly need them…urgently
my mail id is as above
please send the details…

sir,
I am new in this field its very hard to fix components in breadboard referring the above circuit.
so pls can u help me
a video would also be very helpful.
any ideas how i could change the circuit to be as i want it !! reply as soon as possible plz!!
thanks alot in advance…..

Dear Mr.Sitharaman,
Your design circuit is responding well if it is properly installed
in a car. I also installed D1,D2 on front bumper with few modifications
as it is use-full during heavy rush hours in a country like India.
All the Best.

Farokh Kavas or anybody else(who tried this circuit),
I am bit confused with the mounting of transmitter circuit and receiver circuit. How they both will connect to each other and which ports or pins to connect. As per understanding, Transmitter will be installed on front or rear bumper and the receiver circuit should be installed somewhere inside car – on dashboard to be visible to driver.

sir,
could you plss send me the layout and all the neccessary details.. this would be my firt project and i want it to be the best.. but problem is that i am raw and i dont knw much about the things.. i will be vry thankfull if you could be a help..

This circuit does not work well.
I designed the PCB mounted and assembled it. Emitter section generates a signal but is not detected at the input of Receiver section so the unit does not operate as expected. If you want more info you can email me kosmosxxxx@gmail.com
Kind regards

sir,
I am new in this field its very hard to fix components in breadboard referring the above circuit.
So pls can u help me
A video would also be very helpful.
Any ideas how I could change the circuit to be as i want it !! reply as soon as possible plz!!
Thanks alot in advance…..

as the IR photodetector use is not detecting the signal our project is not working properly.wht would b d possible ways to done it?n tell me one thing that the obstacle should some reflective surface like metal or mirror?

Hi happy this works on the received Infrared signal level. The parking sensor transmitter transmits the IR signal which is received, while some close obstacle reflects back the IR signal. The receiver receives as per the signal level received the LEDs glow. Closer the obstacle all the LEds D5, D6, D7 will glow. As the obstacle is moving away little D5 will extinguish if moves away further D6 also will extinguish if it moves further all the will extinguish. Both the transmitters and receiver sensors are mounted on the rear bumper. The electronics are kept in the car drivers panel and can be energised by the car battery when the car is reversing.

sir, can you please send me the following about the parking sensor circuit???
pcb layout
circuit schematics
block diagram
component specifications
i will be very thankful as i require this for my final year project.

laser light is coherent, so as for only a single small dot being reflected back, so maybe use some special concave type lens or something in front of laser, to better the chances that the photodiode can detect it.

This circuit I think will work, except for the viewing angle problems(ie setting it up), and further intensifying the exposure(IR)

But knowing the viewing angles, 60-120 or so degrees will work I believe.

But, what I`d rather do, is use the ir laser diode from a dvd burner, and use some driver circuitry for it, like the 555 used here, doing some modulation. I just believe the ir laser will be better equipped as for intensity.

what if i placed the parking circuit at a point in rear bumper of my car & on parking there is a pole behind my car, not in alingnment of the LEDs, than the circuit will not detect any obstacle…….so how can i use it on full width of my car…..plz ans on my email..

hi sir
i am a student in the lebanses university and i really wana know how to build this thing and put it on a gadget but plus i need instead of glowing on the last 5 mins i want it to change side or to just block in its place !! any ideas how i could change the circuit to be as i want it !! reply as soon as possible plz!!
please mail me the required—-> layal_ghossein@hotmail.com
thanks alot in advance

Hello,
can i know how can the transmitter and the receiver can be place? i have problem to place the two circuit together. besides, i want to know further details about this project. Please mail me the required –> sen92.capricorn@gmail.com
thank you.

Sir,
I’m a beginner and i want to know the more details on this project.Can i know how am i suppose build the receiver and transmitter? and a video would also be helpful to do this project.. Thanks.. please send me email about this project details.. –> sen92.capricorn@gmail.com
once again, thank you..

Sir,
Could you please mail me the details of the project? i am a beginner and was wondering how exactly do the leds respond to change in proximity of the obstacle. could you explain how to implement the above on a bread board? how am i supposed to place the transmitter and receiver. i tried building them separately on two different breadboards but the receiver doesn’t detect anythng. i shall be extremely grateful if you could help me out.

Hi Seetharaman,
Good day,
Just to follow up this request/inquiry dated Jan.24, 2012,
as quoted;
How can I determine the exact distance of the sensor,meaning; from the dashboard to the rear bumper and to any obstacle at the rear of the car.
From the sensor at the dashboard, and to the rear bumper of the car, how many centimeters total all in all?
Thanks .

Hi Seetharaman,
How can I determine the exact distance of the sensor,meaning; from the dashboard to the rear bumper and to any obstacle at the rear of the car.
From the sensor at the dashboard, and to the rear bumper of the car, how many centimeters total all in all?
Thanks .

Hi Jason you need not be very specific about the frequency as this project only senses the level of IR signal received. Not compatible with Ultrasonic sensors you require modifications in both transmitter and receiver circuit.

Everyone wants the audio version of the circuit. The mods needed are very simple. The buzzer can be driven from the 3 lm324 outputs as long as the buzzer current needs are not greater than the output of the lm324. Care must be taken not to over tax the output. Use different resistor sizes to change the ma of current to the buzzer. It will progressively get louder if you start with larger values and decrease the values as you go. Use Ohms law for resistor values. If needed, a transistor hooked from the output can drive larger milliamps to the buzzer. Some buzzers even have two inputs that can be driven. One that pulses and one that is steady. You could increase the sound then pulse when maximum range is reached. A little research and creativity will make the circuit do wonders. Good luck.

Hi Testpen Mount the electronics in the car, place both the sensors as per notes.
The D1 & D2 must be mounted close (~2cm) to each other, looking in same direction.
The D1 can be a general purpose IR LED.
The D2 can be general purpose IR photo diode with sun filter.
The circuit will definitely work.

this site is very good in others comparision but please help me i nee a circuit of wirless rc car with forward and backward 100feet rc range and high speed operated with 9vlt battery if you can do this i will say you excellent tag that circui in your website thankyou

sir admin..can i also have a full copy of this article..
its my project for may last subject..and i can’t finish it.
i can’t make it work.i’m confuse about the parts..like the sun filter,and photo diode..here’s my e-mail add. x0xo_x0xo@yahoo.com

Hi JoySankar, i have transferred energy using laser beam in one of my project, even we could communicate through it, i will search if i still had its diagram,
anywaz if u r intrstd cntct me Badeekh@yahoo.com

hey Peter Davidson, i got ur conserning one, reversing parking buzzer, but problem is that i cudnnt adjust its sensitivity, anyhow u can make it ur self, cntct at Badeekh@yahoo.com
Admin
i got the sheild from a scrap vcd… thx:-)

Hi Patience Karemera hope you are enjoying by assembling and using it successfully. try whenever possible the circuits appearing in Circuitstoday, they are all tested circuits you will find them useful and also will give immense happiness by the results after assembling them.

Hi Richa in my openion you cannot use a capacitor with lower voltage ones, rated voltage is good. higher voltage capacitors can be used sucessfully, but on the long run they may get dried up earlier than the rated ones.

I am student of B.Tech Electronics and Communication Engineering student.We are making a project on Wireless Energy Tranfer. So if it possible on your part to provide us some information along with the circuit diagrams,please help us in making our project.Thanks

Any updates on the buzzer version of this?
Has anyone done it? I’m interested..

All

In case anybody missed it, this circuit activates LED’s instead of the customary audio buzzer that one is used to hearing in cars. And normally the closer you get to the obstacle the more persistant the buzzer becomes. This circuit activates an LED and then the longer the obstacle is present depends on when the 2nd LED swithes on and then the 3rd. Allthough this circuit will work I don’t think it is pratical for when somebody is reversing and looking into their mirrors. It needs conversion to audio.

miniature sun filter sheets are available in the market. You can use a dark cellophane paper or a piece of X ray film for the purpose.
The best source to get a sun filter is your old VCR with remote. Most probably there will be a filter covering its IR sensor.

Parking is a problem at airports and in Australia the airports are owned by the Airport Corporation. They effectively have a monopoly on parking at the airport. What some enterprising individuals have done is sell parking spaces close to the airport and offer a free shuttle service to the terminal. This can be very cost effective and is really taking off in Australia.